Unitary illuminating device



June 30, 1936.

c. H. BRASELTON UNITARY ILLUMINA'IING DEVICE INVENTOR Filed Aug. 25, 1932 Patented June 30, 1936 UNITED STATES 2,046,285 UNITARY IILUMINATING DEVICE Chester H. Braselton, New York, N. Y.,'assignor to Sirian Lamp Company, Newark, N. 1., 'a corporation of Delaware Application August 25, 1932, Serial No. 630,382

7Claims.

This invention relates to illuminating devices and particularly to such devices in which two or more colors are blended together to produce-a third, andis a continuation in part of my co- 5 pending application Serial No. 611,817, filed May One of the objects of the invention is to provide a unitary lamp structure in which several electrical discharges may be carried on independently of each other.

Another object of the invention is to provide an electric illuminating device in which two or more colored lights may be produced independently of each other in one unitary lamp structure- Still another object 01' the invention is to provide an electric lamp having a plurality of en velopes all mounted upon one base so that the lamp as a unit may be screwed into a standard 20,1amp receiving socket.

Other objects of the invention and objects relating to the construction and assembly of the various parts will be apparent as the description of the invention proceeds.

One embodiment of the invention has been 11- lustrated in the accompanying drawing in which:

Fig. 1 is a sectional side elevation of my ini-. proved lamp;

Fig. 2 is a plan view of the lamp with the cap removed;

Fig; 3 -is a sectional plan view taken on. the line 3 3 of Fig. 1; and V Fig. 4 is an expanded view of the three envelopes in perspective showing the manner of making the electrical connections between them.

' Broadly the invention comprises the provision of two or more envelopes each having a pair of electrodes and containing an ionizable gas so 150 as clearly indicated in Fig. 3, so that when the three envelopes are placed together they form a complete cylinder. Each of the envelopes is provided with an angular press l3 at each end thereof whose sides may conform to the straight sides oi the envelope so as to fit together back to back the neon gas at operating temperatures.

as indicated in Figs. 2 and 3. when the three envelopes are placed together, so as to'iorm a single'complete cylinder, the lower ends may be secured in a threaded base plug. by means of suitable cement l5, while the upper ends may 5 be secured in'acap member it also with suitable cement II, the electrical connections being made within the cap it and the base plug it.

The envelope l0 may have an electrode l8 formed of a circular disc of metal, such as nickel, 10 iron, tungsten, or the like, mounted-at the lower I end thereof upon a support rod l9 which is sealed through the lower press. At the other end of the envelope a filamentary resistance wire or heater element 20 may be mounted betweentwo support rods 2| and 22 which are likewise sealed through the upper press. The envelope Ill may be filled with an ionizable, gas having a sufilcient pressure to cause a discharge to appear between the electrode i8 and. the resistance wire 20 when a suit- 2 able potential is produced between the two. Any ionizable gas may be used within the bulb but -I may prefer to use one or more of the monatomic gases such as neon, helium, argon, krypton, or xenon, or a metal vapor such as one of the vapors 25 oi. sodium, caesium, mercury, rubidium, or mixtures of such vapors. As an example of one particular type of lamp the envelope l0 may be filled with neon gas at a'pressure somewhat under 5 mm. of mercury.

The envelope i2 may be exactly similar in construction to the envelope ill but may contain adifferent gas. Thus an electrode 23 similar to the electrode IS in the envelope i0 may be mounted on a support rod 24 which is sealed through the 35 lower press of the envelope l2 whilea filamentary resistance wire or heater element 25 may be mounted between two support rods 26 and 21 which are sealed through the upper press of the envelope I2- The envelope l2 may, in the present I case, be filled with mercury vapor at a pressure which will equal about three times the pressure 01 The mercury may be inserted in the envelope I! ma well known manner, as by leaving a drop of mercury in the envelope when the envelope is sealed The third envelope il may be iormedsimilggly I to the others but a pair of support rods 28 and '29 may be sealed through the lower press while a,

second pair of support rods 30 and 3i may be se'aledthrou'gh the upper press. A filamentary resistance wire 32 may be supported longitudinally oi the envelope between the support rods 28 p and 30 while a second filamentary resistance wire A 33 may be similarly supported between the two support rods 29 and 3|. The envelope ll may preferably be exhausted or provided with a relatively non-conductive inert gas, such as nitrogen,

so that the filaments 32 and 33 may be heated even. to a high light emitting temperature without causing any discharge inside'oi the envelope.

With the envelopes constructed as explained above the three may be positioned in contact with each other as indicated in Figs. 2 and 3 and while .held in this position the electrical connections may bemade. Thus the upper ends of the support rods 22 and 21 in the envelopes I and I2 respectively may be welded together by bending them so as to cross each other and welding at the point 01' crossing. Likewise-the upper end. of the support rod 2| of the envelope it) may be welded to the upper end of the support rod of the envelope II and the upper end of the support rod 3i 0! the envelope l I may be welded to the upper wire 35. The connections may be made in the base 0! the lamp by soldering the wire 34 to the side of the base and the wire to the center contact 38 thereof. I

Thus connected current may enter the wire 34, pass up through the support rod 28 in the envelope l0, through the filamentary resistance wire 32, through the'support rod'3iI at the top oi. the en velope, into the support rod 2i on the top of the envelope l0, down through the resistance wire 20 in that envelope, up through the support rod 22 and'into the support rod 21 of the envelope l2, down through the resistance element 25 in that envelope, up through the support one 26 and into the support rod 3| of the enveflope H, down through the. filamentary resistance wire 33, through the support rod 29 in the bottom of the envelope II, and out through the lead-in wire sideof the filament 32 while the other side oi that filament is connected to the resistance element 20 in the envelope ii, there will be a drop of potential between the element 2ll. and the electrode II in that envelope depending on the resistance of the filament 32. This drop of potential aided by the heat produced by the element 20 will cause a discharge to occur between that element and the electrode it through the neon gas which will have a reddish tint.

A similar phenomenon occurs in the envelope l2 where the electrode 23 isconnected to one side with about three times as much mercury vapor as neon when the lamp is operating.

While the filaments 32 and 33 have been indicated as being identical, the resistance 01' each should be predetermined so as to get the properpotential drop through the gas in the cooperatin'g envelope. In some instancesjtherefore, one wire might be shorter than the other or they may be made of different resistance materials. They also may be arranged to emit light iidesired or they may be so designed that they are not raised to light emitting temperaturebut merely act as a ballast tor the other two envelopes Also if desired the color of the light emitted by the filaments 32 and 33 may be filtered by suitably coloring the glass 01 that envelope so that light from the envelope will be colored with. one of the three primary colors, for instance, the other two envelopes being arranged to emit the other two primary colors so that the three envelopes to-' gether may give a white light. With the arrangement described above, however, the two envelopes I0 and I2 combine to produce the white light by the neon discharge in one and the mercury vapor discharge in the other and the light from the envelope II is used solely to augment the total amount of light.

The combination of colors may be varied considerably to produce not only white light but any desired colored efiect by blending several colors together, or the lamp may be designed to produce*- a single color'as may seem desirable. b

While three envelope are shown and described the invention is not intended to be limited to the three envelopes but may include any number 0! discharge envelopes so connectedand provided with ballasting resistances so that the discharges may be easily started and as easily controlled.

Also while the two ballast resistances are shown as mounted in a single envelope they may each have an individual envelope, if desired, or the envelope or envelopes may. be completely dispensed with and the ballast resistance may be arranged either in the base 01' the lamp or in the cap thereof. Y

The heating element used in the discharge bulbs may be ordinary filaments oi' tungsten or other refractory metal, or they may be coated with electron emitting materials to increase the ionization in the neighborhood thereof so as to start the discharge at lower temperatures.

3 Many other modifications of the invention may be resorted to without departing from the spirit thereof, and I do not desire to limit myself. to what has been shown and described expept as such limitations occur in the appended claims.

J,whatIdesiretoclaimandsecm'ebyLetters.-

Patent. is:

together, a pair of resistance elements, means to connect one of said resistance elements to the end oi one or said heater elements, means to connect of the filament 33 and the heater'elementii is connected to the other side of it, thus making a difierence in potential between the heater element 2! and theelectrode 23 corresponding to the resistance of the filament 33. A discharge willthen occur between the heater 2! and the electrode 23 through the mercury vapor which will have a bluish-green tint. b

The combined light of the envelopes II and I2 may be such as to produce a white light ii" the proportion 61 the gases are as indicat d above the other of said resistance elements tp the other 65 01' said heater el ts, an I ectrode in each of. said envelopes and spaced m said. heater element, means toconnec e ot'said electrodes to the opposite end oi one of said resistance elements, andmeansto connect the other of said electrodes'to the opposite end of the other of said resistance elements.

2. In an electric'lamp an envelope, a heating element within said envelope, an electrode within said envelope spaoedtrom said heating element, 76

a quantity of neon gas within said envelope, a second envelope positioned adjacent said first envelope, a heater element within said second envelope, an electrode within said second envelope and spaced from said heater element, a quantity of mercury within said second envelope, means to connect one end of each of said heater elements together, a resistance element, means to electrically connect said resistance element between the other end of one of said heater elements and the electrode. corresponding to said heater element, a second resistance element, and means to electrically connect said second resistance element between the other end of said second heater element and its corresponding electrode.

3. In an electric lamp a plurality of envelopes arranged about a common axis, a pair of resistance elements mounted in one of said envelopes, a heater element mounted in another of said envelopes, means to connect one end of one of said resistance elements to one end of said heater element, an electrode mounted in said second mentioned envelope and spaced from said heater element, means to connect the other end of said first mentioned resistance element with said electrode. an ionizable gas in said second envelope, a second heater element in a third of said envelopes, means to connect one end of said second heater element with the free end of said first mentioned heater element, means to connect the other end of said second heater element with o: e end of the second of said resistance elements, a second electrode in said third mentioned envelope spaced from said second heater element, means to connect the opposite end of said second resistance element to said second electrode, and an ionizable gas in said third mentioned envelope. 3

4. In an electric lamp an envelope, a heater element within said envelope, an electrode within said. envelope and spaced from said heater element, a quantity of neon gas at apressure less than 5 mm. of mercury within said envelope, a second envelope mounted adjacent said first envelope, a pair of resistance elements within said end of said last mentioned heater element with third envelope mounted adjacent said first two 5 envelopes, a heater element within said envelope,

means to connect one end of said last mentioned heater element with the free endof said first mentioned heater element, means to connect the other one.end of said second resistance element, an electrode within said third envelope and spaced from said heater element, means to connect the opposite end of said second resistance element to said last mentioned electrode, a quantity of mercury within said third envelope having a pressure less than mm. of mercury at operat-.- ing temperatures, and means to support said three envelopes on a common base.

5. A lamp structure comprising three elongated 0 tube sections adapted to be positioned side by side, each tube having a sector cross section and reduced ends, the three sections when combined forming a cylinder, and a holding cap fastened over each of the three adjacent reduced ends of the sections whereby each section is restrained from axial or lateral movement with reference to the other.

6. A lamp comprising three independent and sealed tube sections, each section having a sector cross section and restricted ends, means at each end of said sections for holding them in inter-engaging relationship to form a tubular assembly, and a difierent conductive gas in each tube section;

7. A lamp comprising three independent and sealed tube sections fastened together at their ends, two of said tube sections containing a conducting gas and separated electrodes and the third section containing a solid conductor,-"'and 40 conducting means for connecting said electrodes and solid conductor together.

CHES'I'ER H. BRASELTON. 

